Preliminary Thoughts on the IBM 127-qubit Eagle Quantum Computer

  1. These are only very preliminary impressions based on very limited information, subject to change as more information becomes available
  2. Brief summary
  3. References — The Eagle has landed
  4. Quantum processor vs. quantum computer
  5. Hopes and disappointments
  6. Yes, it’s a significant engineering achievement
  7. Why didn’t reduced crosstalk boost qubit fidelity significantly?
  8. Apparently no significant upgrade to the basic core qubit technology
  9. Uneven progress by IBM’s own standard for progress
  10. Quantum Volume (QV) of 32 is rather disappointing — what can you do with 5 qubits?
  11. Misleading headline: “IBM Rolls Out A Game-Changing 127-Qubit Quantum Computer That Redefines Scale, Quality, And Speed”
  12. Is it true that Eagle can’t be simulated?
  13. Qubit coherence time and circuit depth are secondary priorities for now
  14. Availability?
  15. No hands-on access
  16. Need for a Principles of Operation and detailed technical specifications
  17. What happened to the other five qubits?
  18. Maybe an upgrade to Eagle?
  19. Caveat: All of my direct observations are based on Eagle revision r1 — upgrades could change things
  20. Mediocre measurement fidelity
  21. No dramatic improvement in qubit fidelity
  22. Meanwhile Falcon has been advancing nicely
  23. Preview of Osprey
  24. How exactly do you go about computing Quantum Volume (QV) with more than 50 qubits?
  25. What can you do with 127 (or 65) qubits that you can’t do with 23 qubits?
  26. The world’s most powerful quantum processor?
  27. No, Eagle is not able to offer any dramatic quantum advantage
  28. In short, Eagle offers no net benefit to most real users at present
  29. Twin priorities for the medium term are progress towards quantum Fourier transform and quantum phase estimation as well as progress towards quantum error correction and logical qubits
  30. Progress towards near-perfect qubits will help on both fronts, but Eagle hasn’t done so, yet
  31. Variational methods are a technical dead-end and unlikely to ever achieve any significant quantum advantage
  32. Hopefully Osprey makes more significant progress on both qubit fidelity and fine granularity of phase
  33. Limited qubit connectivity is IBM’s greatest exposure
  34. Are superconducting transmon qubits a technical dead-end for dramatic quantum advantage due to severely limited connectivity? It sure seems that way!
  35. Never say never — I’m sure somebody can up up with a clever way to exploit a majority of Eagle’s qubits
  36. There may be some niche use cases where Eagle can be of significant advantage
  37. Where are all of the 40-qubit quantum algorithms?
  38. Can Eagle support 24 to 29-qubit algorithms?
  39. Can Eagle support 20 to 23-qubit algorithms?
  40. Can Eagle support 15 to 19-qubit algorithms?
  41. Clearly Eagle and IBM are still deep in the pre-commercialization stage of quantum computing, not yet ready to even begin commercialization
  42. The bottom line is that Eagle is still a research project, not close to a commercial product
  43. My advice is to stick with Falcon if you’re not using more than 20 to 24 qubits at present, or better yet, use simulation until Eagle offers significantly better qubit fidelity
  44. Will Eagle set a new world record for hype?
  45. Is Eagle a dud? It’s not THAT bad!
  46. Is Eagle a flop? Well, basically, yes
  47. No, Eagle is not positioned to enable a technical breakout for most users
  48. Did IBM jump the gun? Should they have waited another 3 to 6 or even 9 months? Maybe, maybe not
  49. What’s next for Eagle? Waiting for the r2 revision
  50. Will Eagle r4 hit 3.5 nines of qubit fidelity and support 32-qubit algorithms?
  51. Is Eagle close to offering us practical quantum computing? No, not really
  52. To end on a positive note, we should celebrate IBM’s engineering achievement with Eagle
  53. Summary and conclusions

These are only very preliminary impressions based on very limited information, subject to change as more information becomes available

Brief summary

  1. Significant jump in qubit count to 127. Almost double the qubits of the previous top-end 65-qubit Hummingbird processor.
  2. Broke the 100-qubit barrier.
  3. Significant engineering improvements. At the chip level. Introduction of multi-level fabrication — increases density while reducing crosstalk. As the IBM press release puts it, “breakthrough packaging technology.”
  4. Progress on the path to more physical qubits to support quantum error correction (QEC) and logical qubits.
  1. No significant benefits to most typical near-term quantum algorithm designers or quantum application developers. All of the engineering is under the hood where most typical users won’t see it. Low qubit fidelity — no significant improvement from previous processors — precludes using more than 20 or so qubits in a single circuit — which can already be done with a 27-qubit Falcon, so the dramatic increase in qubit count isn’t generally functionally useful for most typical users, at present.
  2. No hint of any significant change to the basic core qubit technology. Despite the dramatic overall engineering redesign, there is no hint that the core qubit technology has changed. Presumably IBM would have touted that if it had been improved.
  3. No significant increase in qubit fidelity. Some 27-qubit Falcon processors are better.
  4. No hint of improvement in fine granularity of phase and probability amplitude. Needed for quantum Fourier transform (QFT) and quantum phase estimation (QPE), as well as for more complex algorithms utilizing quantum amplitude estimation (QAE). Needed for quantum computational chemistry, so no significant advance on this front.
  5. No hint of any significant improvement in measurement fidelity. Sorely needed.
  6. No improvement in qubit connectivity. Same topology. Low qubit fidelity limits use of SWAP networks to simulate connectivity.
  7. No significant increase in qubit coherence time. Many 27-qubit Falcon processors are better, some by a lot.
  8. No significant improvement in gate execution time. The minimum does seem to show significant improvement, but the average is not quite as good as ibm_hanoi (27-qubit Falcon), although somewhat better than ibmq_brooklyn (65-qubit Hummingbird.)
  9. No significant increase in circuit depth. Follows qubit coherence time and gate execution time.
  10. No improvement in Quantum Volume (QV). Measured at only 32 as of December 8, 2021. Very disappointing. Worse than Falcon (64 and 128). Matches 65-qubit Hummingbird. I had hoped for 256.
  11. No significant progress in two of the three metrics for progress given by IBM. Scale increased, but no significant increase in quality (QV) or speed (CLOPS).
  12. No support for Qiskit Runtime. At least not initially, but I presume that will come, eventually.
  13. Unlikely to attain any substantial degree of quantum advantage. Due to limited qubit fidelity and limited connectivity.
  14. No documented attempt to implement quantum error correction (QEC) or logical qubits.
  15. Clearly Eagle and IBM are still deep in the pre-commercialization stage of quantum computing, not yet ready to even begin commercialization. Many questions and issues and much research remains. Not even close to commercialization.
  16. No roadmap for enhancements to Eagle. Other than Osprey and Condor being successors. But I want to know about r2, r3, r4, and r5.
  1. Engineering achievement for IBM. Required to support higher qubit counts.
  2. Progress towards physical qubit count needed for quantum error correction (QEC) and logical qubits.

References — The Eagle has landed

Quantum processor vs. quantum computer

Hopes and disappointments

  1. Qubit fidelity would be significantly improved.
  2. Qubit coherence time, gate execution time, and circuit depth would be significantly improved.
  1. Improved connectivity. Not sure how since the overall qubit topology was not expected to be any different, and it wasn’t.
  2. Finer granularity of qubit phase. And probability amplitude.

Yes, it’s a significant engineering achievement

  1. Eagle broke the 100-qubit barrier with 127 qubits.
  2. Almost double the qubit count of the previous top-end 65-qubit Hummingbird processor.
  3. Introduction of multi-level chip fabrication. Increases qubit density while reducing crosstalk.
  1. Qubit plane. The qubits themselves.
  2. Resonator plane. The resonators needed to connect and measure the qubits. Although the diagram says “Resonators for qubit readout wired through connectors. Measured shifts in the frequency of the resonator depend on the state of the qubit.”, which speaks to readout (measurement), but not two-qubit gate execution and entanglement.
  3. Wiring plane. Connections to external control electronics.
  4. Interposer plane.Leverages CMOS packaging techniques, including thru-substrate vias, to exploit the third dimension to electrically connect the qubits to the other planes and deliver the signals while protecting their coherence.” Not clear to me what that really means relative to what the wiring plane does — the diagram has a big empty white square!

Why didn’t reduced crosstalk boost qubit fidelity significantly?

Apparently no significant upgrade to the basic core qubit technology

Uneven progress by IBM’s own standard for progress

  • IBM measures progress in quantum computing hardware through three performance attributes: Scale, Quality and Speed. Scale is measured in the number of qubits on a quantum processor and determines how large of a quantum circuit can be run. Quality is measured by Quantum Volume and describes how accurately quantum circuits run on a real quantum device. Speed is measured by CLOPS (Circuit Layer Operations Per Second), a metric IBM introduced in November 2021, and captures the feasibility of running real calculations composed of a large number of quantum circuits.
  • https://newsroom.ibm.com/2021-11-16-IBM-Unveils-Breakthrough-127-Qubit-Quantum-Processor
  1. Scale: Big leap.
  2. Quality: No significant improvement. Quantum Volume (QV) measured at only 32 as of December 8, 2021. Worse than Falcon (64 and 128). Matches 65-qubit Hummingbird.
  3. Speed: Unknown. CLOPS is still not reported as of the time this is written, December 10, 2021. Possibly worse since Qiskit Runtime is not yet supported.

Quantum Volume (QV) of 32 is rather disappointing — what can you do with 5 qubits?

Misleading headline: “IBM Rolls Out A Game-Changing 127-Qubit Quantum Computer That Redefines Scale, Quality, And Speed”

  1. Quantum Volume (QV) of only 32. Compared to 64 and 128 for the 27-qubit Falcon.
  2. Speed not even reported. As of this writing, December 10, 2021, the IBM Quantum Services dashboard for the ibm_washington system does not report a metric value for CLOPS and says that Qiskit Runtime is not supported.

Is it true that Eagle can’t be simulated?

  • ‘Eagle’ is the first IBM quantum processor whose scale makes it impossible for a classical computer to reliably simulate.
  • In fact, the number of classical bits necessary to represent a state on the 127-qubit processor exceeds the total number of atoms in the more than 7.5 billion people alive today.

Qubit coherence time and circuit depth are secondary priorities for now

  1. Qubit fidelity increases dramatically. Long circuits are rather useless if they are noisy.
  2. Connectivity increases dramatically. Longer and more complex circuits imply a significant degree of connectivity, which is not possible at present.

Availability?

  1. System has been tagged as Exploratory.
  2. It has been offline every time I checked.
  3. The dashboard shows that it hasn’t been calibrated for a month now.
  4. No Quantum Volume (QV) is displayed on the dashboard. Initially, as of November 27, 2021, but added as of December 8, 2021 — but only QV of 32, which is worse than Falcon and no better than 65-qubit Hummingbird.
  5. No speed measurement (CLOPS) is displayed on the dashboard.

No hands-on access

Need for a Principles of Operation and detailed technical specifications

  1. Principles of Operation.
  2. Implementation specification.

What happened to the other five qubits?

  1. The physical qubit layout. Where the physical qubits are placed on the chip.
  2. The logical qubit layout. How the physical qubits are connected.

Maybe an upgrade to Eagle?

  1. Negligible improvement in qubit fidelity. Hopefully get much closer to a third nine.
  2. Negligible improvement in coherence time, gate execution time, and circuit depth.
  3. Some preliminary results attempting to implement quantum error correction (QEC). Even if only one or two logical qubits.
  1. No improvement in connectivity.
  2. No improvement in fine granularity of phase. Required for quantum Fourier transform (QFT) and quantum phase estimation (QPE).

Caveat: All of my direct observations are based on Eagle revision r1 — upgrades could change things

  1. ibm_washington
  2. QV 32 — not shown
  3. CLOPS — not shown
  4. Status: Offline
  5. Total pending jobs: 0 jobs
  6. Processor type: Eagle r1
  7. Version: 0.0.1
  8. Basis gates: CX, ID, RZ, SX, X
  9. Avg. CNOT Error: 2.021e-2
  10. Avg. Readout Error: 8.822e-2
  11. Avg. T1: 74.28 us
  12. Avg. T2: 101.43 us
  13. Supports Qiskit Runtime: No
  14. Calibration data Last calibrated: a month ago
  15. Qubit: Frequency (GHz) Avg 5.065 min 4.785 max 5.297
  16. Qubit: T1 (us) Avg 74.28 min 16.54 max 123.11
  17. Qubit: T2 (us) Avg 101.43 min 8.58 max 228.56
  18. Qubit: Readout assignment error Avg 8.822e-2 min 7.000e-3 max 4.856e-1
  19. Connection: CNOT error Avg 2.021e-2 min 8.394e-3 max 3.580e-2
  20. Connection: Gate time (ns) Avg 322.198 min 88.889 max 1457.778
  1. ibm_washington
  2. QV 32 — not shown
  3. CLOPS — not shown
  4. Status: Offline
  5. Total pending jobs: 0 jobs
  6. Processor type: Eagle r1
  7. Version: 0.1.0 — from 0.0.1
  8. Basis gates: CX, ID, RZ, SX, X
  9. Avg. CNOT Error: 2.157e-2 from 2.021e-2
  10. Avg. Readout Error: 2.582e-2 from 8.822e-2
  11. Avg. T1: 95.92 us from 74.28 us
  12. Avg. T2: 103.31 us from 101.43 us
  13. Supports Qiskit Runtime: No
  14. Calibration data Last calibrated: 16 hours ago
  15. Qubit: Frequency (GHz) Avg 5.064 min 4.774 max 5.291 from Avg 5.065 min 4.785 max 5.297
  16. Qubit: T1 (us) Avg 95.92 min 3.86 max 232.85 from Avg 74.28 min 16.54 max 123.11
  17. Qubit: T2 (us) Avg 103.31min 5.16 max 222.36 from 101.43 min 8.58 max 228.56
  18. Qubit: Readout assignment error Avg 2.582e-2 min 2.500e-3 max 2.760e-1 from Avg 8.822e-2 min 7.000e-3 max 4.856e-1
  19. Connection: CNOT error Avg 2.157e-2 min 5.178e-3 max 1.746e-1 from Avg 2.021e-2 min 8.394e-3 max 3.580e-2
  20. Connection: Gate time (ns) Avg 545.351 min 80 max 1187.556 from Avg 322.198 min 88.889 max 1457.778
  1. ibm_washington
  2. QV 32 — for the first time that I noticed as of 3:54 PM ET 12/8/2021
  3. CLOPS — not shown
  4. Status: Online — for the first time that I noticed as of 3:54 PM ET 12/8/2021
  5. Total pending jobs: 0 jobs
  6. Processor type: Eagle r1
  7. Version: 0.1.0
  8. Basis gates: CX, ID, RZ, SX, X
  9. Avg. CNOT Error: 6.717e-1
  10. Avg. Readout Error: 2.347e-2
  11. Avg. T1: 95.9 us
  12. Avg. T2: 103.31 us
  13. Supports Qiskit Runtime: No
  14. Calibration data Last calibrated: 25 minutes ago
  15. Qubit: Frequency (GHz) Avg 5.064 min 4.774 max 5.291
  16. Qubit: T1 (us) Avg 95.9 min 1.27 max 232.85
  17. Qubit: T2 (us) Avg 103.31 min 5.16 max 222.36
  18. Qubit: Readout assignment error Avg 2.347e-2 min 3.000e-3 max 3.215e-1
  19. Connection: CNOT error Avg 6.717e-1 min 5.650e-3 max 1.000e+0
  20. Connection: Gate time (ns) Avg 507.864 min 80 max 1187.556
  1. ibm_washington
  2. QV 32 — no change from its initial value
  3. CLOPS — not shown
  4. Status: Online — Queue paused
  5. Total pending jobs: 0 jobs
  6. Processor type: Eagle r1
  7. Version: 1.1.0 from 0.1.0
  8. Basis gates: CX, ID, RZ, SX, X
  9. Avg. CNOT Error: 3.828e-2 from 6.717e-1
  10. Avg. Readout Error: 2.397e-2 from 2.347e-2
  11. Avg. T1: 94.57 us from 95.9 us
  12. Avg. T2: 102.64 us from 103.31 us
  13. Supports Qiskit Runtime: No
  14. Calibration data Last calibrated: 13 hours ago
  15. Qubit: Frequency (GHz) Avg 5.064 min 4.767 max 5.291
  16. Qubit: T1 (us) Avg 94.57 min 32.31 max 173.21
  17. Qubit: T2 (us) Avg 102.64 min 3.49 max 234.62
  18. Qubit: Readout assignment error Avg 2.397e-2 min 4.700e-3 max 2.470e-1
  19. Connection: CNOT error Avg 3.828e-2 min 5.656e-3 max 1.000e+0
  20. Connection: Gate time (ns) Avg 528.508 min 213.333 max 1187.556
  1. ibm_washington
  2. QV 32 — no change from its initial value
  3. CLOPS 1.1K — shown for the first time
  4. Status: Online
  5. Total pending jobs: 0 jobs
  6. Processor type: Eagle r1
  7. Version: 1.1.0
  8. Basis gates: CX, ID, RZ, SX, X
  9. Avg. CNOT Error: 3.989e-2 from 3.828e-2
  10. Avg. Readout Error: 2.628e-2 from 2.397e-2
  11. Avg. T1: 97.74 us from 94.57 us
  12. Avg. T2: 99.2 us from 102.64 us
  13. Supports Qiskit Runtime: No — odd since CLOPS is now measured
  14. Calibration data Last calibrated: 18 minute ago
  15. Qubit: Frequency (GHz) Avg 5.064 min 4.767 max 5.291 — unchanged
  16. Qubit: T1 (us) Avg 97.74 min 6.11 max 170.38 from Avg 94.57 min 32.31 max 173.21
  17. Qubit: T2 (us) Avg 99.2 min 1.98 max 243.12 from Avg 102.64 min 3.49 max 234.62
  18. Qubit: Readout assignment error Avg 2.628e-2 min 3.400e-3 max 3.909e-1 from Avg 2.397e-2 min 4.700e-3 max 2.470e-1
  19. Connection: Avg 3.989e-2 min 5.498e-3 max 1.000e+0 from CNOT error Avg 3.828e-2 min 5.656e-3 max 1.000e+0
  20. Connection: Avg 547.556 min 213.333 max 1187.556 from Gate time (ns) Avg 528.508 min 213.333 max 1187.556
  1. CNOT between qubits 8 and 9.
  2. CNOT between qubits 9 and 8.
  3. CNOT between qubits 113 and 114.
  4. CNOT between qubits 114 and 113.
  5. CNOT between qubits 114 and 115.
  6. CNOT between qubits 115 and 114.
  1. CNOT between qubits 2 and 3.
  2. CNOT between qubits 3 and 2.
  3. CNOT between qubits 8 and 9. Failed earlier.
  4. CNOT between qubits 9 and 8. Failed earlier.
  5. CNOT between qubits 20 and 21.
  6. CNOT between qubits 21 and 20.
  7. CNOT between qubits 21 and 22.
  8. CNOT between qubits 22 and 21.
  9. CNOT between qubits 113 and 114. Failed earlier.
  10. CNOT between qubits 114 and 113. Failed earlier.
  11. CNOT between qubits 114 and 115. Failed earlier.
  12. CNOT between qubits 115 and 114. Failed earlier.
  1. The system has been online every time I checked today.
  2. Calibrated within the past hour every time I checked.
  3. CNOT error rate has fallen to 1.738e-2 (0.01738, 1.738%) — the lowest I’ve seen so far. It’s been that low whenever I checked so far today, multiple times.
  4. There are no 1.0 100% CNOT error rate spikes. None that I have noticed all day.
  5. The highest CNOT error rate I have seen today was 0.1342–13.42%, for CNOT between qubits 123 and 124.
  6. There were a fair number of qubit pairs (more than a dozen) with an error rate around 5–7%.
  7. Most qubit pairs had a CNOT error rate under 2%.
  8. Some qubit pairs (a minority) had CNOT error rates under 1%.
  9. Average readout (measurement) error rate was 2.826e-2 (0.02826, 2.826%) roughly in line with previous days.
  10. Oddly, CLOPS was down to 850 — all day.
  11. Has shown 1 job pending every time I’ve refreshed the display.
  12. No other notable changes.

Mediocre measurement fidelity

  • Avg. Readout Error: 2.347e-2

No dramatic improvement in qubit fidelity

  1. Connection: CNOT error Avg 2.021e-2 min 8.394e-3 max 3.580e-2.
  2. Connection: CNOT error Avg 2.157e-2 min 5.178e-3 max 1.746e-1.
  3. Connection: CNOT error Avg 6.717e-1 min 5.650e-3 max 1.000e+0.
  4. Connection: CNOT error Avg 3.828e-2 min 5.656e-3 max 1.000e+0.
  1. Only modestly better than some of the 27-qubit Falcon averages.
  2. Worse than the rest of the Falcon averages.
  3. Not even two nines — only 1.8 nines.

Meanwhile Falcon has been advancing nicely

Preview of Osprey

  1. It will have 433 qubits.
  2. It requires the IBM Quantum System Two hardware infrastructure.
  3. It is expected sometime in 2022. Likely at the IBM Quantum Summit 2022, which I presume will once again occur in November as the 2021 Summit did.
  1. Any improvements in qubit fidelity.
  2. Any improvements in coherence time, gate execution time, or circuit depth.
  3. Any improvements in fine granularity of phase or probability amplitude.
  4. Any improvements in measurement fidelity.
  5. Any improvements in connectivity. Unlikely since it would be a radical architectural change, not an evolutionary step.
  6. Any improvements in Quantum Volume (QV).

How exactly do you go about computing Quantum Volume (QV) with more than 50 qubits?

What can you do with 127 (or 65) qubits that you can’t do with 23 qubits?

The world’s most powerful quantum processor?

No, Eagle is not able to offer any dramatic quantum advantage

  1. Limited qubit fidelity.
  2. Limited qubit connectivity.

In short, Eagle offers no net benefit to most real users at present

Twin priorities for the medium term are progress towards quantum Fourier transform and quantum phase estimation as well as progress towards quantum error correction and logical qubits

Progress towards near-perfect qubits will help on both fronts, but Eagle hasn’t done so, yet

Variational methods are a technical dead-end and unlikely to ever achieve any significant quantum advantage

Run multiple circuits at the same time?

Hopefully Osprey makes more significant progress on both qubit fidelity and fine granularity of phase

Limited qubit connectivity is IBM’s greatest exposure

Are superconducting transmon qubits a technical dead-end for dramatic quantum advantage due to severely limited connectivity? It sure seems that way!

Never say never — I’m sure somebody can up up with a clever way to exploit a majority of Eagle’s qubits

There may be some niche use cases where Eagle can be of significant advantage

Where are all of the 40-qubit quantum algorithms?

Can Eagle support 24 to 29-qubit algorithms?

Can Eagle support 20 to 23-qubit algorithms?

Can Eagle support 15 to 19-qubit algorithms?

Clearly Eagle and IBM are still deep in the pre-commercialization stage of quantum computing, not yet ready to even begin commercialization

The bottom line is that Eagle is still a research project, not close to a commercial product

My advice is to stick with Falcon if you’re not using more than 20 to 24 qubits at present, or better yet, use simulation until Eagle offers significantly better qubit fidelity

Will Eagle set a new world record for hype?

Is Eagle a dud? It’s not THAT bad!

Is Eagle a flop? Well, basically, yes

No, Eagle is not positioned to enable a technical breakout for most users

  1. Qubit fidelity.
  2. Gate fidelity.
  3. Qubit connectivity.
  4. Measurement fidelity.

Did IBM jump the gun? Should they have waited another 3 to 6 or even 9 months? Maybe, maybe not

  1. Delay the product while additional enhancements are added.
  2. Delay additional enhancements in favor of an earlier release of the product.
  • In every project there comes a time to shoot the engineers and ship the product.

What’s next for Eagle? Waiting for the r2 revision

Will Eagle r4 hit 3.5 nines of qubit fidelity and support 32-qubit algorithms?

  1. 3.5 nines of qubit fidelity.
  2. Support for 32-qubit algorithms. 3.5 nines of qubit fidelity is likely the primary obstacle.

Is Eagle close to offering us practical quantum computing? No, not really

To end on a positive note, we should celebrate IBM’s engineering achievement with Eagle

  1. Significant jump in qubit count to 127. Almost double the qubits of the previous top-end 65-qubit Hummingbird processor.
  2. Broke the 100-qubit barrier. Getting all of those qubits to work at all is an amazing achievement.
  3. Significant engineering improvements. At the chip level. Introduction of multi-level fabrication — increases density while reducing crosstalk. As the IBM press release puts it, “breakthrough packaging technology.”
  4. Progress on the path to more physical qubits to support quantum error correction (QEC) and logical qubits.

Summary and conclusions

  1. In short, Eagle offers no significant net benefit to most typical near-term quantum algorithm designers or quantum application developers. That could change if Eagle is upgraded, but this is where revision r1 of Eagle stands right now. Despite the dramatic increase in raw qubit count, the lack of any significant improvement in qubit fidelity or qubit connectivity renders those additional qubits effectively useless for most users.
  2. Eagle is an impressive engineering accomplishment. Couldn’t have achieved 127 qubits without the dramatic processor redesign.
  3. But all of the engineering is under the hood where most typical users won’t see it. The dramatic increase in qubit count isn’t generally functionally useful to most typical users, at present.
  4. It’s a decent stepping stone towards quantum error correction (QEC) and logical qubits. QEC needs a lot more qubits. Eagle is a decent start down that path.
  5. But lackluster qubit fidelity and mediocre qubit connectivity prevent Eagle from having any significant and dramatic benefit to real users over 27-qubit Falcon. Most users won’t be able to effectively use more qubits on Eagle than they can on Falcon.
  6. No hint of any significant change to the basic core qubit technology. Despite the dramatic overall engineering redesign, there is no hint that the core qubit technology has changed. Presumably IBM would have touted it if it had been improved.
  7. No dramatic improvement in qubit fidelity. Only modestly better than some of the 27-qubit Falcons. Worse than the rest of the Falcons. Not even two nines — only 1.8 nines.
  8. No dramatic improvement in coherence time, gate execution time, or circuit depth.
  9. Sorry, but Eagle won’t deliver any substantial quantum advantage. Mostly due to limited qubit fidelity and limited qubit connectivity. There are certainly enough qubits, but that’s not good enough.
  10. Quantum Volume (QV) of 32 is rather disappointing. Same as the 65-qubit Hummingbird. Less than the QV of 64 and 128 for the 27-qubit Falcon. I had hoped for at least 256. Maybe r2 or r3 might yield some improvement?
  11. Curious that there is no support for Qiskit Runtime. At least not initially, but I presume that will come, eventually. Especially surprising since IBM has made a big deal about performance (speed) and CLOPS. No CLOPS rating either, presumably because it depends on Qiskit Runtime (I think.)
  12. Incremental enhancements, as happened with Falcon, could change this picture, possibly dramatically.
  13. But even then, trapped-ion and neutral atom qubits could overtake superconducting transmon qubits simply as a result of full any to any connectivity. Memo to IBM: Qubit connectivity is a really REALLY big deal.
  14. It will be interesting to see whether the 433-qubit Osprey will be a dramatic improvement over Eagle or only a modest to moderate improvement.
  15. Twin priorities for the medium term are progress towards quantum Fourier transform (QFT) and quantum phase estimation (QPE) as well as progress towards quantum error correction (QEC) and logical qubits. Technical progress is needed in both qubit fidelity and fine granularity of phase. But we aren’t seeing much progress on either front yet by Eagle.
  16. Progress towards near-perfect qubits will help on both fronts, but Eagle hasn’t done so.
  17. I sure hope Osprey makes more significant progress on both qubit fidelity and fine granularity of phase. But, I’m not holding my breath.
  18. Don’t discount the possibility that some clever algorithm designer may come up with a very creative algorithm which actually is able to exploit a majority of Eagle’s qubits to solve some practical real-world problem. Even more than 24 or 32 qubits. I’d settle for a 40-qubit algorithm which can also be simulated — provided that it is automatically scalable so that it can trivially exploit more capable hardware when it becomes available.
  19. There may be some niche use cases where Eagle can be of significant advantage. But I don’t know of any, at present. Something that is very tolerant of or even exploits noisy qubits.
  20. My advice is to stick with Falcon if you’re not using more than 20 to 24 qubits at present, or better yet, use simulation until Eagle offers significantly better qubit fidelity. Being able to simulate up to 32 to 40 qubits with greater qubit fidelity is more compelling than Eagle at this stage.
  21. No, Eagle is not positioned to enable a technical breakout for most users. The dramatic increase in qubit count alone just won’t do it. What’s missing are dramatic improvements in: qubit fidelity, gate fidelity, qubit connectivity, and measurement fidelity. Dramatic improvements in all of those areas would lead to a true technical breakout.
  22. Clearly Eagle and IBM are still deep in the pre-commercialization stage of quantum computing, not yet ready to even begin commercialization. Many questions and issues and much research remains. Not even close to commercialization.
  23. Is Eagle close to offering us practical quantum computing? No, not really. It’s an increment of progress, but we have very far to go.
  24. To end on a positive note, we should celebrate IBM’s engineering achievement with Eagle. It really is quite impressive from an engineering perspective.
  25. So, stay tuned. It ain’t over yet.

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Freelance Consultant

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Jack Krupansky

Jack Krupansky

Freelance Consultant

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